update sources to Ubuntu-5.0.0-27.28

(generated with debian/scripts/import-upstream-tag)

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/submodules/ubuntu-disco b/submodules/ubuntu-disco
index 22841660d41ea82504450d636ef68b12a4fbdcac..caa19397f6eb68a4f9bb252eceb5b4c0f23f1512 160000 (submodule)
--- a/submodules/ubuntu-disco
+++ b/submodules/ubuntu-disco
@@ -1 +1 @@
-Subproject commit 22841660d41ea82504450d636ef68b12a4fbdcac
+Subproject commit caa19397f6eb68a4f9bb252eceb5b4c0f23f1512